Markets are on a crazy, sugar-fuelled journey…’When the music stops,” Chuck Prince famously observed back in mid-2007, “things will get complicated”.

The then chief executive of the US banking giant Citigroup was admitting that growing concerns about sub-prime loans could ultimately shatter what we now know was “irrational exuberance” on global financial markets.

“As long as the music is playing, though, you’ve got to get up and dance,” Prince continued. “And we’re still dancing.”

There’s a “we’re still dancing” mood on global markets today, just as there was six years ago in the run-up to what turned out to be the disastrous market meltdown of September 2008.

Rather than the securitisation of recklessly extended commercial credit providing the music, the beat now comes from “quantitative easing”, courtesy of the world’s leading central banks.

The Dow Jones Industrial Average is up 15pc since last September, after the Federal Reserve launched QE3, its third round of money-printing. The eurozone’s Stoxx 50 has soared also, gaining 30pc since July, when European Central Bank (ECB) president Mario Draghi vowed to do “whatever it takes” to save the euro.

The Nikkei 225 has rocketed 44pc since late December, after the election of a new government committed to forcing the Bank of Japan to crank up its QE antics. The UK’s FTSE 100, too, has gained 20pc in six months, riding a wave of Bank of England largesse — and, crucially, the prospect of more to come.